The problem with all the gear ratio charts that I have seen so far, including RaptorZone, is that they do not take into account the tire size. They are really useless when you are trying to figure out what combination of front and rear sprocket sizes will result in the same ratio when you change tire sizes.

 

Joe,
I did the following to figure out the difference in gearing caused by changing tire height:
Circumference of a tire= (2*Pi)*R (R=radius)
So, for a 20inch tall tire: 6.28 * 10 = 62.8
(the ATV travels 62.8 inches for one revolution of the tire)
For a 22 inch tall tire: 6.28 * 11 = 69.08
(the ATV travels 69.08 inches for revolution of the tire)
This is exactly a 10 percent change in gearing (makes sense because a 22 inch tire is exactly 10 percent taller than a 20 inch tire). Going from a 12 tooth front sprocket to an 11 tooth front sprocket is an 8 percent reduction in gearing, so if you do both, you end up with 2 percent HIGHER
gearing than when you started. Since you then changed your rear sprocket from a 40 tooth to a 44 tooth, which lowered the gearing by 10 percent again, your final total change was to lower your gearing by 8 percent. In other words:
12 tooth front to 11 tooth front=8% lower gearing
20 inch to 22 inch tires= 10% higher gearing
40 to 44 tooth rear sprocket=10% lower gearing
For a total change of 8% lower gearing.
This looks like exactly what I would want to do to get the Raptor final gearing down where I want it, as long as I don't have to lower the skid plate much to clear the bigger rear sprocket.

Good luck,
Lorrin Lee

 

I will send it your way. Tell me how you like the chart.